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Table 2 Baseline characteristics of all participants and by randomly assigned intervention groups

From: The effects of fatty fish intake on adolescents’ nutritional status and associations with attention performance: results from the FINS-TEENS randomized controlled trial

Variables Number All Fish Meat Supplement P a
Characteristics
Gender n (%) 415      0.546
 Male   195 (47.0) 56 (43.8) 73 (50.3) 66 (46.5)  
 Female   220 (53.0) 72 (56.3) 72 (49.7) 76 (53.5)  
Age (years) 415 14.6 ± 0.3 14.6 ± 0.3 14.6 ± 0.3 14.6 ± 0.3 0.531
BMI (kg/m2) 385 19.8 ± 3.0 19.8 ± 3.4 19.7 ± 2.3 19.9 ± 3.1 0.940
Parental education level n (%) 341      0.793
 Elementary/vocational school 132 (38.7) 41 (39.4) 47 (40.5) 44 (36.4)  
 College/university   209 (61.3) 63 (60.6) 69 (59.5) 77 (63.6)  
Family income in NOKb n (%) 338      0.201
  < 200,000–749,999   70 (20.7) 21 (20.4) 17 (14.8) 32 (26.7)  
 750,000–1,249,999   171 (50.6) 50 (48.5) 66 (57.4) 55 (45.8)  
 1,250,000- > 2,000,000   97 (28.7) 32 (31.1) 32 (27.8) 33 (27.5)  
Immigrantc n (%) 341 7 (2.1) 2 (1.6) 2 (1.7) 3 (2.5) 0.914
Nutritional status
LA, 18:2n-6 (%) 415 10.8 ± 1.3 10.8 ± 1.4 10.8 ± 1.2 10.9 ± 1.3 0.707
AA, 20:4n-6 (%) 415 15.6 ± 1.5 15.6 ± 1.4 15.6 ± 1.6 15.6 ± 1.5 0.958
EPA, 20:5n-3 (%) 415 0.9 ± 0.4 0.9 ± 0.3 0.9 ± 0.4 0.9 ± 0.4 0.960
DPA, 22:5n-3 (%) 415 2.4 ± 0.3 2.4 ± 0.3 2.4 ± 0.3 2.3 ± 0.3 0.110
DHA, 22:6n-3 (%) 415 4.9 ± 1.1 4.9 ± 1.0 5.0 ± 1.2 4.8 ± 1.0 0.171
Omega-3 indexd 415 5.8 ± 1.3 5.8 ± 1.2 5.9 ± 1.4 5.7 ± 1.3 0.304
  ≤ 8 n (%)   395 (95.2) 122 (95.3) 135 (93.1) 138 (97.2) 0.271
s-25(OH)D (nmol/L) 424 48.8 ± 17.4 49.1 ± 17.1 49.7 ± 17.8 48.3 ± 17.4 0.671
  < 50 nmol/L n (%)e   229 (54.0) 72 (54.5) 76 (52.1) 81 (55.5) 0.832
s-Ferritin (μg/l) 412 40.7 ± 23.1 40.9 ± 22.4 41.2 ± 24.5 40.4 ± 22.3 0.953
 <  15 μg/l n (%)e   40 (9.7) 12 (9.4) 13 (9.2) 15 (10.6) 0.912
UIC (μg/L) 415 122.6 ± 63.7 122.6 ± 71.3 122.9 ± 59.3 125.0 ± 66.7 0.693
  < 100 μg/le   164 (39.5) 55 (42.6) 49 (34.3) 60 (42.0) 0.282
Dietary intake 414      
Fish for dinnerf   1.5 (0.9) 1.5 (1.0) 1.4 (0.9) 1.5 (0.9) 0.780
Herring/mackerel/salmon for dinnerf   1.0 (0.9) 1.0 (1.0) 0.9 (0.9) 1.0 (1.0) 0.852
Fish as bread spreadf   0.6 (1.0) 0.7 (1.0) 0.6 (1.0) 0.6 (0.9) 0.620
Fish oil supplements (n (%))g 413      0.659
 Never   220 (53.3) 60 (46.9) 81 (56.3) 79 (56.0)  
 1–3 times/month   53 (12.8) 18 (14.1) 18 (12.5) 17 (12.1)  
 1–3 times/week   45 (10.9) 19 (14.8) 14 (9.7) 12 (8.5)  
 4–6 times/week   20 (4.8) 6 (4.7) 5 (3.5) 9 (6.4)  
 Every day   75 (18.2) 25 (19.5) 26 (18.1) 24 (17.0)  
  1. Abbreviations: AA arachidonic acid, LA linoleic acid, EPA eicosapentaenoic acid, DPA Docosapentaenoic acid, DHA docosahexaenoic acid, 25(OH)D 25-hydroxyvitamin D, s-Ferritin serum ferritin, UIC urinary iodine concentration, NOK Norwegian kroner
  2. aOne-way ANOVA test (continuous variables) and Pearson’s Chi-square test (X2) (categorical variables) for comparison between treatment groups
  3. b100 NOK = approximately 10€/11$
  4. cImmigrant was defined as participants who’s both parents and themselves were born outside Norway
  5. dThe content of EPA and DHA expressed as percent of total fatty acids [6]
  6. eAdolescents were classified with vitamin D deficiency if s-25(OH)D < 50 nmol/L [5], with depleted iron stores if s-ferritin < 15 μg/L [29] and as iodine deficient if UIC < 100 μg/L [28]
  7. fReported meals per week (besides the intervention)
  8. gN (%) of participants reporting to consume fish oil as dietary supplements
  9. Data are given as mean ± SD if not other is indicated